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Not Right For WatchKnowLearn
Ages: 14 - 18
Area of Diagonal-Generated Triangles of Rectangle are Equal
From YouTube, produced by Sal Khan
In this video, Mr. Khan draws a box and two intersecting lines that produce several triangles. Mr. Khan proves that the area of these diagonal-generated triangles of the rectangle are equal. He goes over the formula for finding the area of a triangle... [more]
July 18, 2010 at 03:14 PM
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Not Right For WatchKnowLearn
Ages: 16 - 18
Circumcenter of a Triangle - Khan Academy
From YouTube, produced by Salman Khan
Multiple proofs showing that a point is on a perpendicular bisector of a segment if and only if it is equidistant from the endpoints. Then, using this to establish the circumcenter, circumradius, and circumcircle for a triangle. (12:29)
October 7, 2011 at 11:28 PM
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Not Right For WatchKnowLearn
Ages: 11 - 16
Triangles Overview
From Slideboom, produced by Glencoe- McGraw Hill
This slide show presentation explores the properties of triangles, classifying them, and models solving several problems involving triangles.  This is part of a textbook series put out by Glenco/ McGraw-Hill.
July 30, 2009 at 12:32 PM
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Not Right For WatchKnowLearn
Ages: 11 - 15
Similar Triangles - Khan Academy
From YouTube, produced by Salman Khan
Video uses an electronic black board with different colored pens.  This video is an introduction to similar triangles. The person discusses the meaning of the term similar then goes on to discuss similar triangles (they have all the same angles), and... [more]
Found by Barb in Triangles
July 13, 2009 at 06:30 PM
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Not Right For WatchKnowLearn
Ages: 3 - 8
Learning Shapes - Triangle
From YouTube, produced by Little Runners
This learning shapes video from Little Runners focuses on the attributes of triangles. It shows a picture on the screen of a triangle and a voice talks about the corners and sides of triangles. The video ends with animated images of real-life example... [more]
Found by CKR11 in Triangles
July 24, 2009 at 09:59 AM
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Not Right For WatchKnowLearn
Ages: 12 - 18
Finding The Midsegment of a Triangle
From YouTube, produced by Yourteacher.com
In this vdeo students learn the following theorems related to parallel lines. If 3 parallel lines form congruent segments along one transversal, then they form congruent segments along every transversal. If a line intersects the midpoint of one side ... [more]
February 2, 2010 at 09:13 AM
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Not Right For WatchKnowLearn
Ages: 12 - 18
Overlapping Triangles
From YouTube, produced by Pascale Ngo
The instructor uses a smartboard to demonstrate what overlapping triangles are and their properties.   The room is dark, hence the video is a little dark. The instructor teaches grade 9 Geometry at Martin Luther High School in Maspeth, NY.
March 27, 2010 at 03:58 PM
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Not Right For WatchKnowLearn
Ages: 9 - 13
Scalene Triangles (Interactive)
From pbs.org, produced by MathActive
Identify the properties of two- and three- dimensional geometric figures using appropriate terminology and vocabulary. Classify triangles ad scalene, isosceles, or equilateral.
July 17, 2012 at 03:58 PM
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Not Right For WatchKnowLearn
Ages: 3 - 8
Triangle Song
From YouTube, produced by Have Fun Teaching
This 'rap' song helps students remember the properties of a rhombus. (02:23)
Found by utvol in Triangles
August 20, 2012 at 12:58 AM
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Not Right For WatchKnowLearn
Ages: 3 - 7
Sesame Street: Dancing With Triangles -- Shapes For Younger Learners
From YouTube, produced by Sesame Street Workshop
This is an amusing spoof of 'Dancing With the Stars'. This Sesame Street video shows a dance competition that is supposed to involve triangles, but the contestants are a little confused. Other shapes such as a hexagon and a square are introduced, in ... [more]
May 30, 2010 at 07:41 PM
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